W61906-2RS bearing: complete specifications & equivalents
The W61906-2RS is a ISO 15 radial bearing sized 30 x 47 x 9 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 30 mm |
| Outer diameter D | 47 mm |
| Width B | 9 mm |
| Material | SS440C |
| Seal / shield | 2RS |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 6.24 kN |
| Basic static load rating C0 | 5 kN |
| Fatigue load limit Pu | 0.212 kN |
| Limiting speed (mechanical) | 8500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 47 g |
| Manufacturer designation | W 61906-2RS1 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 61900-series range
| Bore d | 1.181 in |
|---|---|
| Outer diameter D | 1.85 in |
| Width B | 0.354 in |
| ISO bore code | 06 |
| Radial section height (D−d)/2 | 8.5 mm |
| Smallest bore in 61900-series | 3 mm |
| Largest outer diameter in 61900-series | 1120 mm |
| Width range across 61900-series | 3–118 mm |
| Bore position in 61900-series (smallest first) | 14 of 63 |
| Bore above smallest 61900-series size | 27 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61906-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | NSK NSK 6906ZZ shares the 30×47×9 mm envelope but carries different catalogue ratings (6.24/5 kN vs 7.95/5 kN) — the stainless execution is not a load-rating equivalent. |
| W61906 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 30×47×9 mm envelope and equivalent catalogue ratings; W 61906 is the open arrangement execution of this size — boundary dimensions interchangeable, only the seal/shield/cage execution differs. |
| 61906 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF SKF 61906 shares the 30×47×9 mm envelope but carries different catalogue ratings (6.24/5 kN vs 7.28/4.55 kN) — the stainless execution is not a load-rating equivalent. |
| 61906-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF SKF 61906-2RS1 shares the 30×47×9 mm envelope but carries different catalogue ratings (6.24/5 kN vs 7.28/4.55 kN) — the stainless execution is not a load-rating equivalent. |
| 61906-RSR | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF SKF 61906-2RZ shares the 30×47×9 mm envelope but carries different catalogue ratings (6.24/5 kN vs 7.28/4.55 kN) — the stainless execution is not a load-rating equivalent. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the W61906-2RS model number is decoded
The W prefix denotes SKF stainless steel deep-groove bearings (X108CrMo17 / AISI 440C class rings). In the 61900-series, the last two digits encode the bore: 61906 carries code 06 = 30 mm (code × 5). Envelope 30×47×9 mm (1.181×1.85×0.354 in), C 6.24 kN, C0 5 kN, Pu 0.212 kN; limiting speed 8500 r/min and mass 47 g. SKF catalogues the sealed execution as W 61906-2RS1: two contact elastomer lips (2RS1/2RSH spelling) over a lifetime grease fill; the lips add drag, and no reference (thermal) speed is published. Stainless is chosen for corrosion and washdown duty, not for extra load — the same-envelope chrome-steel bearing rates higher.
Typical equipment & failure modes
Common applications
- chemical and marine atmospheres
- medical and laboratory devices
- small pumps handling corrosive media
- bicycle and outdoor equipment
Known failure patterns
- surface staining and pitting when even the stainless steel is left unlubricated in salty or acidic duty
- seal and grease failure before the rings corrode in sustained washdown service
- contact-seal lip hardening and pre-grease loss after long high-temperature service
- grease-life expiry inside the sealed-for-life cavity, which has no relubrication path
Selection pitfalls — read before you substitute
- Stainless bearings carry lower load ratings than chrome steel of the same envelope: W61906-2RS is quoted at C 6.24 kN versus the 9 mm-wide 52100 version — do not swap on dimensions alone.
- Food, pharmaceutical and washdown positions need food-grade grease (e.g. NSF H1 registered) inside W61906-2RS; standard fill is industrial grease unless specified otherwise.
- Corrosion resistance depends on clean, undamaged surfaces: never weld near W61906-2RS or scratch the raceways during mounting, since the damaged spot starts corrosion.
- Temperatures above roughly 300 °C temper the stainless races; even standard greases fail far earlier — keep W61906-2RS inside the quoted grease temperature range.
- Catalogue ratings for W61906-2RS (C 6.24 kN, C0 5 kN) are SKF figures from PUB BU/P1 17000; geometry revisions can change ratings without changing the designation, so keep the catalogue edition with the specification.
- Fillet radii must clear the W61906-2RS chamfer so the 9 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
Frequently asked questions
What are the dimensions of the stainless W61906-2RS?
SKF W 61906-2RS1 measures 30×47×9 mm (1.181×1.85×0.354 in), about 47 g, C 6.24 kN.
What does the W in W 61906-2RS1 mean?
W is the SKF prefix for stainless steel deep-groove bearings (rings in X108CrMo17 / AISI 440C class); the rest of the designation follows the normal series and bore rules.
Can I replace a chrome-steel bearing with stainless W61906-2RS?
The envelope matches, but stainless rates lower (C 6.24 kN for W 61906-2RS1); for corrosive environments that trade-off is intended, for high loads it shortens life.
Is the stainless bearing magnetic?
Yes. Bearing stainless steels are martensitic (hardened) and magnetic; non-magnetic austenitic grades cannot be hardened enough for raceways and balls.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.